The present invention relates to a feeder-breaker apparatus and method for use in the hydraulic mining of friable materials such as coal, tar sands and uranium. It is particularly directed to such an apparatus and method wherein the mined product is reduced to a pumpable form so that it may be pumped under pressure without dependence upon gravity for its conveyance.
In its more particular aspects, the invention is directed to a feeder-breaker wherein breakage of the product is achieved through a principal, high-capacity, single-stage breaker, followed by a secondary breaker. This successive breaker arrangement, as well as the separation steps employed therewith, enables the feeder-breaker to maintain a capacity commensurate with that of high-capacity, single-stage breakers.
The invention is especially concerned with an improvement of mining apparatus and method of the type disclosed in co-pending U.S. patent application Ser. No. 597,985, filed July 22, 1975, by Arthur A. T. Grimley (corresponding to Canadian Application Ser. No. 212,253, filed Oct. 25, 1974). That application discloses a feeder-breaker wherein the breaker is provided with primary and secondary jet monitors, a conveyor, and a breaker mechanism to reduce the size of the mined aggregate being treated. It is not, however, concerned with reducing the mined aggregate to a pumpable form. Rather, it employs a flumed discharge and, thus, is dependent upon the influence of gravity for the ultimate conveyance of the mined product.
Another development relating to the present invention is disclosed in my application Ser. No. 702,072, filed July 2, 1976 and entitled HYDRAULIC MINING APPARATUS AND METHOD. That application discloses a feeder-breaker method and apparatus wherein the mined product is separated into a pumpable constituent and a dry conveyable constituent. To the extent that it separates the pumpable constituent, it is somewhat similar to the invention of the present application. It does not, however, reduce the entire product to a pumpable form.